/******************************************************************************
 * Copyright 2018 The Apollo Authors. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *****************************************************************************/

/**
 * @file
 * Modified function input and used only some functions
 **/
#pragma once

#include <vector>
#include <Eigen/Core>

class PiecewiseLinearKernel
{
public:
    PiecewiseLinearKernel(const uint32_t dimension, const double unit_segment);

    void AddRegularization(const double param);

    const Eigen::MatrixXd &kernel_matrix() const;
    const Eigen::MatrixXd &offset_matrix() const;

    void AddSecondOrderDerivativeMatrix(const double init_derivative,
                                        const double weight);
    void AddThirdOrderDerivativeMatrix(const double init_derivative,
                                       const double init_second_derivative,
                                       const double weight);

    // reference line kernel
    bool AddReferenceLineKernelMatrix(const std::vector<uint32_t> &index_list,
                                      const std::vector<double> &pos_list,
                                      const double weight);

private:
    const uint32_t dimension_;
    const double unit_segment_;
    Eigen::MatrixXd kernel_matrix_;
    Eigen::MatrixXd offset_matrix_;
};